Views and Techniques Flashcards
WHAT IS A SURFACE DEVLOPMENT
Any geometric form which has been ‘unfolded’ so it can be cut and formed from a single piece of paper. They can be produced manually or using CAD software. However, to create the surface development, you have to move the 3D model from CAD to a surface development software.
ORTHOGRAPHIC PROJECTION IN 2D
Shows 3 dimensional objects as two dimensional drawings. They are accurate and detailed. The most common type of orthographi projection is third angle projection.
Third angle projection: Four 2D views, elevation, plan, 2x end elevations.
Bounce lines should be drawn at 45^.
Views should all be aligned and titled. Text should be no larger than 4mm.
Outlines should be 1pt. Centre, dimensions or construction lines should be 0.5pt.
You must include a pictorial view with no hidden detail and a title.
Title box: Drawing title, Project title, Name, School, Course, Scale, Page, Dimension measurement, Date, Third angle projection.
WHAT IS A TRUE SHAPE
A section that will show its true shape when viewed straight on to the profile.
TYPES OF PICTORIAL DRAWINGS
Isometric: All three surfaces are shown. Draw from an isometric crate (lengths and breadths at 30^).
Planometric: Clear view looking down from above. Often used by architects and civil engineers to show a clear view of internal space.
Oblique: Shows the true front view or an object (breadth at 45). Breadths are reduced to half the actual size
One point, two point.
WHAT IS A SECTIONAL VIEW
A sectional view is a view which shows internal detail after an object has been cut by a cutting plane. (Cross hatching at 45^, approximately 5mm apart).
Don’t hatch webs (used to strengthen or support various components
Do not show hidden detail on a sectional view.
Don’t hatch/section webs, nuts, bolts, spindles, bearings or axles.
Sometimes CAD doesn’t realise not to hatch an axle etc. Sometimes it needs to be edited.
WHAT IS AN EXPLODED VIEW
It is a type of assembly drawing which shows the parts separated along a connecting axis or plane. They can be orthographic or pictorial. They show how a product is assembled. They are known as technical detail. Parts should not overlap.
